Collet actuating device for machine tools



Nov. 28, 1944. R, EVANS 2,363,721

COLLET ACTUATING DEVICE FOR MACHINE TOOLS Filed Feb. 1, 1944 2 Sheets-Sheet l INVENTOR 30 5r A? @W ATTORNEYS Nov. 28, 1944. R. EyANs 2,363,721

COLLET ACTUATING DEVICE FOR MACHINE TOOLS Filed Feb; 1, 1944 2 Sheets-Sheet 2 ATTORNEYS tion, on an enlarged-scald: I 7 is a section the're'oi nline Tie-1,. 6. Fig. 8 is a fragmentary sectional elevation of a.

ii ie c l]construction.

Patented Nov. 28, 1944 i TACTUATIN DEVIG MR y MACHINE TOOLS i w t Leigh R. j Evansl Elmira, N. Y., assignor to Karidinge Brothers,;. Inc., Elmira, Y.

Y Applicatim i Februaryfll, 1944, Serial No. 5,201,12 1 y fec amiswlcizts sii This invention relates to mechanism for operl ating collets onllathes andsimilar machinesto open and close the" jaws thereof while the machine is running.

One ofthe objects of this invention is to pro? .vide a positive and reliable quick acting and quickly adjustable mechanism for' collets of lath-es and similar machines. Another; object is tion of whichhas threaded? engagement with to provide a mechanism of this type hich] centrifugalforce tends to'hold the partsrnore securely in locked. position to prevent opening of? the collet when theymachineis in operation. It] is also an object of; this invention to prjovicle mechanism of this typ'e having an improved and; stronger ratchet mechanism for yieldingly hold ing the collet draw tube in adjusted. relation to the spindle Of themaichi'ne.

Otherobjectsand advantages or t inventi n a will appear from" the" following description and claims. V t

In the accompanying drawings:

Fig. 1 is a fragmentary sectional; elevation of i acollet actuating device embodying this @IIVQH".

tion.

Fig! 2 is a fragmentary endi elevationthereofi Fig. 3 is a fragmentary elevationthereof, sim j pi thememel ilar to. Fig. 1,,b-ut showing the parts anism in different positions.

ig. 4, is a sectional. elevation thereof flori line .302 Fig. 5 is a perspective view, o'rtan enlarge'dj scale, of one of the dogs or. latchesiemployed in the mechanism. 1 a

Fig. 6 is a fragmentary sectionalelevation of"? a collet' actuatifig..device of modified: construe,

collet actuatingmechanism of still another mod- Fig. 9 is a section thereof online; 9 9, FigQ-B.

- In Fig. 1.. I- have shown one embodiment :of'

improved mechanism as appliedto the headstock 1210f alathe, but it willbe understood.- that this .inventionmay be; applied to any machine 114- repre-g.

tool inl which colletsmay be used.

1 m thework or a tool same in the direction of its length while this tube is rotating. Any suitable connection may sents the spindle. of. the lathe which is suitably:

-journalled in. the headstock, for example, by.

means of ball bearings 5, ancl 16, which rotatably l support thesspin dle and which. also hold, the spindle against endwise; movement relatively to l the headstock by any suitable means, such f or; example as an. annular. shoulder l1 formed on.

a the. spindle itself; which engages with the inner race'on the ball hearing. L6, and a nut. lll,.-a.por-

I he openingtand apart of the spindle andhwhi'ch engagesqtlie inner face of the ball bearing-; [9 represents a locknutwhich may be employed forholdingthe nut 1-8 against turning on the spindle: The

spindlemay berotated'by any sliitableor 'de sired means, not shownirrtheaccompanying drawings. other suitable'means forrotat ably mounting the spindle a *mach in'e t'ool-Y andfor holdingth'e spindle against endwisemovement maybe employed in place of those shown.

representsthecollet: which may be or any usualor suitable constructiomand which is provi'ded with a beveled"orinclined* annular face 2|" e-led inner surface '220; the spind e. The jaws" of thecolle'tare normally hel'cl'in theirfopen position by their own resiliency and may be moved toward each" other into positionftp grip y drawingthecolletito the left in'rigqi. i i

The opening. closing of the iaws off the collet is usu ny accomplished fby means are i draw tube which has anlinternallyfthreaded. portion 26 engaging. with a. corresponding externally threadeddend portion oi. the collet-l q. The draw tube25 has aslidingflt inthe spindle and extends beyond the left end of the spindle in Figs. 1. and- 3; and the collet draw tube may be provided. at.- this end: thereof with: a jknurled: knob orhand; wheel 21- by means3.:0f which the draw tube! can beturned' relatively to thellathe spindle H; i

the spindle-and inr onder totprovide fora quick). opening and closingof: the=collet, a hand-lever 3D-is" providedgthat shown" being pivoted fat" 31 onone end of a1ink 32,;the other -endofwhich is pivoted on the headstock I 2 in the 'construction shown. Thishanti lever 3U'isprovided with enlarged circular portion through-which the collet draw" tube extejriqfs-an which is conbe employed between the lever and" the. drawv tube. For examplepin'*theconstruction shown.

the lever may;belgconnecteclto al in 35fl means of trunnions or screws 36and' thisring,

which may beformed; in two halves suitably secured together, may be arranged within an .3111: nular. groove or recesst forme d' inpa sleevei 3-11 which is rotatably and slidably mounted? cm the T OFFICE Y closingcof thecolleti eftected by-( movement of. the draw tube lengthwise off draw tube. This sleeve has an annular inclined or beveled portion 38.

The collet draw tube also has rigidly mounted thereon adjacent to the sleeve 31 a ratchet shell 40 having internal ratchet teeth, and the spindle M has secured thereto an extension 4| provided with an outwardly extending flange portion 42 which has one or more dogs or latches which cooperate with the ratchet teeth or the shell to releasably hold the spindle and tube in the desired relation to each other. The sleeve 4| is I as clearly shown in Fig. 4, so that this space proheld against turning relatively to the spindle by" any suitable means, such as a key 43 engaging in wrelatively .to' the ring 51.

a keyway in a spindle and the sleeve preferably has an internal shoulder which abuts against the end of the spindle so that thrusts'against the sleeve will be transmitted to the spindle.

vides room for the dogs or latches 54 to move Since these dogs or latches are of rectangular cross section and operate in similar radial grooves in the ring 51,

. it is obvious that they will be held from turning Suitable means are provided .on the ratchet shell to exert a thrust against the flange 42 of the sleeve or extension 4| of the spindle to pull the collet draw tube to the left from the position shown in Fig. 1, to draw the jaws of the collet toward each other. radial portion .44 of the ratchet shell has a plurality of levers 45 pivoted thereonat 45. end of each lever has acam or eccentric portion 4] thereon which may react against thefiange 42 of the spindle extension 4|, and the other end of each lever 45 is provided with a radially inwardly extending arm 48 which may engage the beveled portion 38 of the slidable sleeve 31. Consequently, when the hand le ver is swung to the left from the position shown in Fig. 1 into the position shown in Fig. 3, the ends 48 of the small levers 45 willbe forced to move radially outwardly'from the axis of the collet draw tube,

thus forcing the cam portions 41 ofthese levers to react against the fiange'42, thus causing the ratchet shell to be moved to the left and drawingthe collet, 2| into the flaring end 22 of the lathe spindle intoaclosed 'or gripping position. The ratchet shell may be held against 'e'ndwise movement relatively, to the c'ollet tube by any suitable means, such for'examp'le as a shouldered portion 50 on this tube.

Since the movement produced by means of the hand lever 30'and thesmall levers is necessarily small and merely=serves to cause the "collet to grip the work or tool, it is important that the collet draw tube and the collet'be insuch adjusted relation to the spindle |4 that.this-limitedmovernent by means ofthe hand lever -will be-suficient to causelthe colletto gripthe work ortooi with the For this reason, accurate-adjustdesired force. ment of the collet. lengthwise of the draw tube by means. of the cooperating threaded portions 26 is necessary. .This adjustment of the collet and its draw tube relatively-t0 the lathe spindle can be effected by means. of the correct positioning of the ratchet sleeve 40 with reference to the flange or disk 42 of the spindle, and this adjustment may be effected by turning theratchet shell 40 relativelyto the disk 42. When these two parts are adjusted into the desired position, they are; releasably held in such position by suitable teeth on the shell 40!" These dogs or latches are urged outwardly by means of springs 55, and in the construction shown in Figs. '1 to 5, these dogs For this purpose, the

One

ratchet shell 40.

in the ringso that the outer edges or teeth 64 of the latches will at all times remain parallel to the ratchet teeth on the inner face of the Any other suitable or desired means may be provided for mounting the dogs or latches on the flange ordisk 42. 1

In the modified constructih shownin Figs. 6 and 7, the ratchet shell 40 cooperates with dogs of modified construction. Inthese figures, the body portions ofthe dogs are of cylindrical shape and fit into round holes formed in an outwardly extending flange 10 formed on asleeve or tubular extension II which issecuredt'o the spindle. The dogs or'latches 12 are bored out from their inner ends to receive the springs I3, and each dog is also provided at opposite sides thereof with end of the dog or ratchet insuch a manner as I I to urge the dogs or ratchets. outwardly.

Another modified form of dog orlatch is shown in Figs. 8 and 9, in'whicha flange or disk '85 is formed on a sleeve 8| secured to the spindle, and

.5 in which the flange is provided with one or more only one dog 'or latch being shown in Figs. 8 and in a direction in which the tooth 85 will engage with the ratchet teeth of the shell 40.

In the use of the apparatus described; if a collet is desired to grip a certain type of workpiece, it iSffiISt necessary to seat the collet so that the jaws will grip the workpiece securely when the hand lever 3|) is in theposition shown in Fig. 3,'and to release the workpiece when the hand lever is in the position shown in'Fig. 1.

In order to accomplish this, the collet andspindle may beheld against rotation while the ratchet shell 4!] is'turned. This will result in" V a a turning'of the threaded part 26 of the collet When the desired 'positionfof the collet relatively 'f to the draw tube 25-is-attained, it-ismerelf necessaryto release 'the shell. The dogs or latches 1 of" the flange of the sleeve secured the spindle willthen'engage with the teeth of. thearatchet shell so as to hold the" draw tube andspindle in desired relationto each other; workpiecestmay then beg ppedme aha: 5- quickly movingacollet draw tube relatively to time by thecolletby first placing them intoi the open jaws of the, collet and then pushing the .hand lever .30 to the left. Thehand wheel or knob 21 may serve asa stop to limit theextent towhich the lever may be movedyto the left or collet closing position. During thismovement tube lengthwise said collet. t H v 3. In an opening and closing device for a collet of said'spindle to open and close of a lathe or similar machine having means for a spindleu for openingand closing the collet, that improvement for adjusting the collet relatively tpthe spindle which comprises a ratchet shell,

secured on the draw tube and having internal;

ratchet teeth, and adog carrying member on the a lathe f spindle having a toothed dog arranged of the ratchet shell relatively to the sp ndle, the

teeth of the dogs will slide lengthwise along the; teethof the ratchet disk. After the required work has beendone, the workpieces are released by again pushing, the hand lever to the right. The construction: described has the advantagethat the work can be very quickly gripped bythe collet and released therefrom by merely actuating the hand lever, and the collet can be quickly adjusted relatively to the draw tube by merely turning the ratchet shell relatively to the spindle and the collet. The dogs or latches which cooperate with the ratchet teethon the shell are all so arranged that when the spindle is rotating, centrifugal force will, augment the action of the springs urging the dogs outwardl so that the higher the speed of the spindle, the

more rigidly the dogs engage the teeth of the ratchet disk 48 and prevent relative rotary motion between the spindle and draw tube. By

preventing the dogs orlatches from turning,iit

thereon with its tooth movable inwardly and outwardly in a substantially radial direction to engage the ratchet teeth of said shellQtopermit adjustment of said draw tube relatively to said colletand said spindle andto hold said draw tube t ,adjustedrelation to said collet'and spindle.

4. In an opening and closing device fora collet of a lathe or similar machine having means for quickly moving a collet draw tube relatively to a spindle for opening and closing the collet, that improvement for adjusting the colletrelatively to the spindle which comprises a ratchet shell secured on the draw tube andhaving' internal ratchet teeth, an outwardly extending flange on said spindle and which extends within said shell,

a plurality of dogs on said flange having toothed portions formed for engagement with the teeth of said shelland arranged to be urged outwardly by centrifugal force when said spindle is rotating, and means for yieldingly urging said toothed will be impossible for the latch teeth to get out of parallel relation to the teeth on the' ratchet shell 40 so that the tendency of the teeth to become broken or unevenly worn will be avoided. The construction described is sufficiently sturdy so that the operator may adjust the collet by grasping the ratchet shell 40 while rotating the spindle I4 by means of the usual power drive, so that very quick adjustment is possible. l a

I claim as my invention: 1. In a quick acting and quickly adjustable opening and closing device for a collet of a lathe,

or similar machine having a hollow rotary spindle and a collet draw tubetherein, that improvement which includes a ratchet shell rigidly mounted on said draw tube adjacent to an end of said spindle, and having ratchet teeth on an inner face thereof extending substantially parallel to said draw tube, an outwardlyextending flange on said spindle, a dog mounted on said flange for engagement with said ratchet teeth to releasably hold said draw tube in the desired relation to said spindle, and lever actuated portions outwardly, into engagement with said shell, said dogs permitting rotation of said shell: relatively to said flange for adjusting said collet relatively to said spindle and yieldingly holding said shell in adjusted spindle.

5. In an opening andclosing device for a collet of a lathe or similar machine having means for quickly moving a collet draw tube, relatively to a spindle for opening and closing the collet, that improvement for adjusting the collet relatively means for moving said collet tube lengthwise relatively to said spindle to open and close said collet. t

2. In a quick acting and quickly adjustable opening and closing device for a collet of a lathe or similar machine having a hollow rotary spindle and a, collet draw tube therein, thatimprovement which includes a ratchet shell rigidly mounted on said draw tube adjacent to an end of said spindle, and having ratchet teeth on an inner face thereof extending substantially parallel to said draw tube, an outwardly extending flange arranged withinsaid shell and mounted on said spindle, a dog on said flange and urged outwardly into engagement with the ratchet teeth of said shell for yieldingly holding said tube and spindle against .relative rotary motion, and means for imparting limited movement of said to the spindle which comprises a ratchet shell secured on the draw tube anduhaving internal ratchet teeth, an outwardly extending flange on 1 said spindle and which extends within said shell,

a plurality of dogs on said flange having toothed portions formed for engagement with theteeth of said shell and arranged to be urged outwardly bycentrifugal force when said spindle is rotating, a ring on-saidflange and havingsubstantially radial recesses formed therein and .in which said dogs are slidable, and means for yieldingly,

urging said dogs outwardly into engagement 3 withsaid teeth ofsaid ratchet shell.

6. A mechanism accordingto claim 5 in which said dogs are of rectangular cross section and said radial recesses are of similar cross sectional form to hold said dogs against turning in said recesses.

7. In an opening and closing device for a collet of a lathe or similar machine having means for quickly moving a collet draw tuberelatively to a spindle for opening and closing the collet, that improvement for adjusting the collet relatively to the spindle which comprises a ratchet shell secured on the draw tube and having internal ratchet teeth, an outwardly extending flange on, said spindle and which extends within said shell,

said flange having a plurality of substantially radial holes therein, dogs arranged in said holeshaving teeth for engaging the teeth of said shell, springs said holesfor urging said dogs outrelation to said collet and it wardly into engagement with the teeth of said shell, and means for holding said dogs against turning in said holes. I

8. In an opening andclosing device for a collet of a lathe or similar machine having means for quickly moving a collet draw tube relatively to a spindle "for opening and closing the collet, that improvement for adjusting the collet relatively to the spindle which comprises a ratchet shell secured on the draw tube and having internal ratchet teeth, an outwardly extending flange on said spindle and which extends within said shell, a dog pivoted on'said flange and having a tooth movable into and out of engagement with said' shel1when said dog swings on its pivot, and yielding means urging said dog to swing on its pivot into'enga'gement with the teeth of said shell.

quickly moving a collet draw tube relatively .to'

a spindle for opening and closing the collet, that improvement for adjusting the collet relatively to the spindle which comprises a ratchet shell secured on the draw tube and having internal ratchet teeth, an outwardly extending flange on I.

said spindle and which extends within said shell, said flange having a slot extending inwardly from its periphery, a toothed dog in said slot and pivoted on said flange to swing to permit the tooth thereof. to engage the teeth of said ratchet shell, and means for urging said dog to swing into engagement with the teeth of said shell.

LEIGH R. 

